And I'm Robert Siegel. President Vladimir Putin travelled to Crimea today to mark the anniversary of Russia's victory in the Second World War. It was his first time there since the peninsula was annexed by Russia. His visit was criticized by the Ukrainian government and Washington, but Putin told Crimeans that by being together with Russia, they're stronger.

PRESIDENT VLADIMIR PUTIN: (Speaking foreign language)

SIEGEL: The annexation of Crimea followed a referendum in March. Next door in Eastern Ukraine, pro-Russian activists are planning similar referendums for Sunday. NPR's Soraya Sarhaddi Nelson reports from Donetsk on the preparations.

SORAYA SARHADDI NELSON, BYLINE: To hear pro-Russian activists tell it, they are all set to hold Sunday's referendum on independence from Ukraine, even though the Kiev government and its western allies continue to denounce it as illegal. Roman Logan(ph) is an election official with the self-proclaimed Donetsk People's Republic, who says they've printed 3 million ballots that are being delivered to 1200 polling stations across the region.

ROMAN LOGAN: (Speaking foreign language)

NELSON: He says 15,000 volunteers will run the election, which he adds will be transparent and meet international standards. But a half hour drive south in the small town of (unintelligible) preparations have barely begun. Pro-Russian activists have set up a small tent in front of town hall here. Inside, a handful of volunteers answer people's questions.

NATALIA LUBENITSKYA: (Speaking foreign language)

NELSON: One is Natalia Lubenitskya(ph) who says she hands out flyers to as many people as she can explaining how the pro-Western government in Kiev doesn't represent people's interest. Another flyer lists the single question pro-Russian activists want Eastern Ukrainian voters to answer. Do you support the independence proclamation of the Donetsk People's Republic?

Where those will cast their ballots is still unclear. Yuri Leksturis(ph) who is the local representative to the Donetsk People's Republic Council says they won't be setting up polling stations until an hour before opening on Sunday.

YURI LEKSTURIS: (Speaking foreign language)

NELSON: He claims they don't need permission from their local government, which is still under Kiev's authority to enter schools and community centers where votes in Ukrainian elections are normally cast. But to avoid confrontations with officials or police, he said they will set up ballot boxes outside the entrances, that way the vote will also be transparent, Leksturis adds.

Elsewhere in Donetsk, the pro-Russian separatists are reported to be less accommodating.

GOVERNOR SERGEI TARUTA: (Speaking foreign language)

NELSON: Governor Sergei Taruta tells reporters that masked separatists are threatening school officials to try and make them give up their buildings for the referendum. He praised those officials for refusing to back down in the face of danger. His administration later told principals not to fight back if they are approached by pro-Russian activists wanting to set up polling stations in their schools and to instead limit their access to a single floor.

But talk of the referendum in Donetsk was quickly set aside after clashes erupted in the regional port city of Mariupol. There are said to be fatalities on both sides after fighting between government forces and pro-Russian gunmen who Ukraine's interior minister said were trying to storm the police station. Soraya Sarhaddi Nelson, NPR News, Donetsk. Transcript provided by NPR, Copyright NPR.